Supports for wind tunnel models of the present type are known, e.g., from U.S. Pat. No. 4,658 635. In wind tunnels wherein models of aircraft or vehicles are tested for their aerodynamic properties, the model is supported in the air flow, by mounting it on a holding arm (often referred to as a sting) which typically penetrates the model body with minimum distortion to the geometric shape. To measure the aerodynamic forces acting on the model, a balance having several degrees of freedom is placed between the sting and the model. This allows the measurement of forces and moments acting on the model (such as drag, sideforce, lift, roll, pitch and yaw), which result from the flow over the model. The elements of the balance are subjected to elastic deformations which are measured by sensors, such as strain gauges and transformed into electric signals representing the respective forces and moments.
Since the wind tunnel model and the balance form an vibrating mass-spring system, the wind tunnel model experiences vibrations which can be excited by the flow and/or the model support. In this manner, longitudinal vibrations as well as torsional vibrations and flexural vibrations are generated.
In said model support known from U.S. Pat. No. 4,658635, the balance for measuring the above mentioned forces is mounted internally in the model. This balance is engaged by the sting which is fastened to a support which itself is supported in a fixed position. Thus, the overall model support comprises the balance, the sting and the support with all of these pans being arranged in series. The support can be excited from signals measured by sensors describing the movement of the model, so that counter vibrations to the resulting vibrations of the model are generated and vibration compensation is effected. The support according to the invention is a very complex structure having numerous degrees of freedom, each of them requiring a separate actuator. Internal balances adapted for mounting on the sting of a wind-tunnel model support, and also such balances provided with piezoelectric sensors, are known from German Patent 31 51 669 C3 and U.S. Pat. No. 4,938,059.
It is an object of the invention to provide a support for wind tunnel models which, due to a novel design of the counter vibration generator, can be given a small-sized and compact configuration.